The atmosphere is fun - it screams natural and artistic like something out of Portland. Their menu is even made of leather. The rooftop, when open, is my favorite place to get a drink in the summertime. You're surrounded by the sights and sounds of 4th Street and drinking some of the best libations money can buy.
I would give their service 5 stars. The staff is warm and friendly, and they are so knowledgeable. USE THEM - tell them what kind of taste and substance you are in the mood for, and they can pick something off their menu and it will surely not disappoint.
The food is amazing. They start you off with bread with some of the best-tasting EVOO I've ever had. I love Love LOVE the mushroom risotto. Their pommes frites never disappoint either. Their desserts are the best in town, but they are so small they always leave me wanting more.
My only beef with Greenhouse (pun intended) is the value. You have to get multiple courses if you want to leave full, and the prices are not modest. Tack on some drinks and wine and you're talking $80 or so per person. Yet, I find myself going back again and again.